794 research outputs found

    Metal-free sp(3) C-H functionalization: a novel approach for the syntheses of selenide ethers and thioesters from methyl arenes

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    A DTBP-promoted metal-free and solvent-free formation of C-Se and C-S bonds through sp(3) C-H functionalization of methyl arenes with diselenides and disulfides is described

    Procalcitonin as a marker of bacterial infection in the emergency department: an observational study

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    INTRODUCTION: Procalcitonin (PCT) has been proposed as a marker of infection in critically ill patients; its level is related to the severity of infection. We evaluated the value of PCT as a marker of bacterial infection for emergency department patients. METHODS: This prospective observational study consecutively enrolled 120 adult atraumatic patients admitted through the emergency department of a 3000-bed tertiary university hospital in May 2001. Fifty-eight patients were infected and 49 patients were not infected. The white blood cell counts, the serum C-reactive protein (CRP) level (mg/l), and the PCT level (ng/ml) were compared between the infected and noninfected groups of patients. RESULTS: A white blood cell count >12,000/mm(3 )or <4000/mm(3 )was present in 36.2% of the infected patients and in 18.4% of the noninfected patients. The best cut-off serum levels for PCT and CRP, identified using the Youden's Index, were 0.6 ng/ml and 60 mg/l, respectively. Compared with CRP, PCT had a comparable sensitivity (69.5% versus 67.2%), a lower specificity (64.6% versus 93.9%), and a lower area under the receiver operating characteristic curve (0.689 versus 0.879). PCT levels, but not CRP levels, were significantly higher in bacteremic and septic shock patients. Multivariate logistic regression identified that a PCT level ≥ 2.6 ng/ml was independently associated with the development of septic shock (odds ratio, 38.3; 95% confidence interval, 5.6–263.5; P < 0.001). CONCLUSIONS: PCT is not a better marker of bacterial infection than CRP for adult emergency department patients, but it is a useful marker of the severity of infection

    Constraints on the cosmological parameters with three-parameter correlation of Gamma-ray bursts

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    As one of the most energetic and brightest events, gamma-ray bursts (GRBs) can be treated as a promising probe of the high-redshift universe. Similar to type Ia supernovae (SNe Ia), GRBs with same physical origin could be treated as standard candles. We select GRB samples with the same physical origin, which are divided into two groups. One group is consisted of 31 GRBs with a plateau phase feature of a constant luminosity followed by a decay index of about -2 in the X-ray afterglow light curves, and the other has 50 GRBs with a shallow decay phase in the optical light curves. For the selected GRB samples, we confirm that there is a tight correlation between the plateau luminosity L0L_0, the end time of plateau tbt_b and the isotropic energy release Eγ,isoE_{\gamma,iso}. We also find that the L0tbEγ,isoL_0-t_b-E_{\gamma,iso} correlation is insensitive to the cosmological parameters and no valid limitations on the cosmological parameters can be obtained using this correlation. We explore a new three-parameter correlation L0L_0, tbt_b, and the spectral peak energy in the rest frame Ep,iE_{p,i} (L0tbEp,iL_0-t_b-E_{p,i}), and find that this correlation can be used as a standard candle to constrain the cosmological parameters. By employing the optical sample only, we find the constraints of Ωm=0.6970.278+0.402(1σ)\Omega_m = 0.697_{-0.278}^{+0.402}(1\sigma) for a flat Λ\LambdaCDM model. For the non-flat Λ\LambdaCDM model, the best-fitting results are Ωm=0.7130.278+0.346\Omega_m = 0.713_{-0.278}^{+0.346}, ΩΛ=0.9810.580+0.379(1σ)\Omega_{\Lambda} = 0.981_{-0.580}^{+0.379}(1\sigma). For the combination of the X-ray and optical smaples, we find Ωm=0.3130.125+0.179(1σ)\Omega_m = 0.313_{-0.125}^{+0.179}(1\sigma) for a flat Λ\LambdaCDM model, and Ωm=0.3440.112+0.176\Omega_m = 0.344_{-0.112}^{+0.176}, ΩΛ=0.7700.416+0.366(1σ)\Omega_{\Lambda} = 0.770_{-0.416}^{+0.366}(1\sigma) for a non-flat Λ\LambdaCDM model.Comment: Accepted for publication in The Astrophysical Journal, 13 pages, 9 figures and 2 table

    A bibliometric analysis of studies on the gut microbiota in cardiovascular disease from 2004 to 2022

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    BackgroundIncreasing evidence indicates that the gut microbiota (GM) is linked to cardiovascular disease (CVD). Many studies on the GM in CVD have been published in the last decade. However, bibliometric analysis in this field is still lacking.MethodsOn 30 September 2022, a search of the Web of Science™ (WoS; Clarivate™, Philadelphia, PA, USA) yielded 1,500 articles and reviews on the GM and CVD. Microsoft Excel and CiteSpace and VOSviewer software were used to analyze publication trends and research hotspots in this field.ResultsOur search generated 1,708 publications on the GM in CVD published between 2004 and 2022, and 1,500 articles and review papers were included in the final analysis. The number of publications relating to the GM in CVD increased from 1 in 2004 to 350 in 2021. China (485 publications, 9,728 non-self-citations, and an H-index of 47) and the USA (418 publications, 24,918 non-self-citations, and an H-index of 82) contributed 32.31%, and 27.85%, respectively, of the total number of publications. Examination of the number of publications (Np) and number of citations, excluding self-citations (Nc), of individual authors showed that Y. L. Tian (Np: 18, Nc: 262, and H-index: 12), from China, is the most productive author, followed by R. Knight (Np: 16, Nc: 3,036, and H-index: 15) and M. Nieuwdorp (Np: 16, Nc: 503, and H-index: 9). The Chinese Academy of Medical Sciences and Peking Union Medical College accounted for the largest number of publications (Np: 62, Nc: 3,727, and H-index: 13, average citation number (ACN): 60.11). The journal Nutrients had the most publications (Np: 73, Nc: 2,036, and ACN: 27.89). The emerging keywords in this field were “monooxygenase 3” (strength 3.24, 2020–2022), “short-chain fatty acid” (strength 4.63, 2021–2022), “fatty liver disease” (strength 3.18, 2021–2022), “metabolic disease” (strength 3.04, 2021–2022), “Mediterranean diet” (strength 2.95, 2021–2022), “prevention” (strength 2.77, 2021–2022), and “intestinal barrier” (strength 2.8, 2021–2022).ConclusionPublications on the GM in CVD rapidly increased in the last decade. The USA was the most influential country in publications in this field, followed by China. The journal with the most publications was Nutrients. Monooxygenase-3, short-chain fatty acids, fatty liver disease, metabolic disease, the Mediterranean diet, intestinal barrier, and prevention are the current hotspots or potential hotspots for future study

    The Role of Endoplasmic Reticulum Stress in Autoimmune-Mediated Beta-Cell Destruction in Type 1 Diabetes

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    Unlike type 2 diabetes which is caused by the loss of insulin sensitivity, type 1 diabetes (T1D) is manifested by the absolute deficiency of insulin secretion due to the loss of β mass by autoimmune response against β-cell self-antigens. Although significant advancement has been made in understanding the pathoetiology for type 1 diabetes, the exact mechanisms underlying autoimmune-mediated β-cell destruction, however, are yet to be fully addressed. Accumulated evidence demonstrates that endoplasmic reticulum (ER) stress plays an essential role in autoimmune-mediated β-cell destruction. There is also evidence supporting that ER stress regulates the functionality of immune cells relevant to autoimmune progression during T1D development. In this paper, we intend to address the role of ER stress in autoimmune-mediated β-cell destruction during the course of type 1 diabetes. The potential implication of ER stress in modulating autoimmune response will be also discussed. We will further dissect the possible pathways implicated in the induction of ER stress and summarize the potential mechanisms underlying ER stress for mediation of β-cell destruction. A better understanding of the role for ER stress in T1D pathoetiology would have great potential aimed at developing effective therapeutic approaches for the prevention/intervention of this devastating disorder

    Radio Plateaus in Gamma-Ray Burst Afterglows and Their Application in Cosmology

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    The plateau phase in the radio afterglows has been observed in very few gamma-ray bursts (GRBs), and 27 radio light curves with plateau phase were acquired from the published literature in this article. We obtain the related parameters of the radio plateau, such as temporal indexes during the plateau phase (α1\alpha_1 and α2\alpha_2), break time (\Tbz) and the corresponding radio flux (FbF_{\rm b}). The two parameter Dainotti relation between the break time of the plateau and the corresponding break luminosity (\Lbz) in radio band is \Lbz \propto \Tbz^{-1.20\pm0.24}. Including the isotropic energy \Eiso and the peak energy \Epi, the three parameter correlations for the radio plateaus are written as \Lbz \propto \Tbz^{-1.01 \pm 0.24} \Eiso^{0.18 \pm 0.09} and \Lbz \propto \Tbz^{-1.18 \pm 0.27} \Epi^{0.05 \pm 0.28}, respectively. The correlations are less consistent with that of X-ray and optical plateaus, implying that radio plateaus may have a different physical mechanism. The typical frequencies crossing the observational band may be a reasonable hypothesis that causes the breaks of the radio afterglows. We calibrate GRBs empirical luminosity correlations as standard candle for constraining cosmological parameters, and find that our samples can constrain the flat Λ\LambdaCDM model well, while are not sensitive to non-flat Λ{\Lambda}CDM model. By combining GRBs with other probes, such as SN and CMB, the constraints on cosmological parameters are \om = 0.297\pm0.006 for the flat Λ{\Lambda}CDM model and \om = 0.283\pm0.008, \oL = 0.711\pm0.006 for the non-flat Λ{\Lambda}CDM model, respectively.Comment: 16 pages, 6 figures and 6 tables, accepted for publication in Ap

    Allogeneic hematopoietic stem cell transplantation for acute leukemia with Gilbert's syndrome

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    Acute leukemia with coexisting Gilbert's syndrome treated by allogeneic hematopoietic stem cell transplantation (allo-HSCT) is rarely reported. Here we described a case whose transaminase levels were almost normal, although transient hyperbilirubinemia repeatedly happened during chemotherapy
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